Vein Dissecting Device and Method

ABSTRACT

A vein harvesting assembly for harvesting a vein in a body comprises: a dissecting member, with the dissecting member being insertable into the body and moved along a vein to dissect tissue surrounding the vein. A covering member possesses a proximal end portion and a distal end portion, with the covering member possessing a covered space extending from the proximal end portion to the distal end portion, and the covering member being mountable on and movable along the dissecting member when the dissecting member is positioned in a living body. A cutting member is comprised of an elongated member and a blade member so that rotation of the elongated member results in turning of the cutting member to cut tissue surrounding the vein. The cutting member is insertable into the space in the covering member and is movable in a distal direction along the space.

This application claims priority under 35 U.S.C. §119(e) to U.S.Provisional Application No. 62/240,663, U.S. Provisional Application No.62/240,668, U.S. Provisional Application No. 62/240,797, and U.S.Provisional Application No. 62/240,834 filed on Oct. 13, 2015, theentire content of each of which is incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a device for dissecting or harvestinga vein in a living body.

BACKGROUND DISCUSSION

It is known to use an artery graft (e.g., internal thoracic artery,gastroepiploic artery and radial artery) or a vein graft (e.g., greatsaphenous vein) as a bypass vessel in performing vascular bypassgrafting at the heart (coronary artery bypass grafting: CABG). It hasbeen reported that. at present, artery grafts (particularly, internalthoracic artery) offer higher long-term patency rates than vein grafts.Vein grafts are commonly thought to be poor in long-term patency rate.In recent years, however, it has been reported that the long-termpatency rate of vein grafts is enhanced when the vein graft is harvestedin a state in which the vein is covered by surrounding tissue (forexample, fat, connective tissue, tissue between a skin layer and amuscle layer, tissue between a skin layer and an interosseous membrane,branch vessels, etc.) and is used as a bypass vessel while remainingcovered with the tissue.

Generally speaking, there are two primary techniques for harvestingblood vessels such as the saphenous vein. One technique is referred toas open vein harvesting. This technique involves making an elongatedincision along, for example, the patient's limb (leg), and then carryingout the harvesting procedure for removing the blood vessel from thepatient's limb. This technique has been found to be somewhat problematicin that it is rather invasive, requiring a rather extensive incision inthe patient's limb. Harvesting site complications (e.g., infections) arealso not uncommon.

Another technique is referred to as endoscopic vein harvesting. Thistechnique has some advantages over open vein harvesting in that theendoscopic vein harvesting is less invasive and has been found to have alower incidence of infection. Unfortunately, endoscopic vein harvestingexhibits a lower patency rate because the harvested vein tends to bemore damaged.

SUMMARY

The devices and methods disclosed here provide a technique having animproved patency rate similar to the patency rate with the open veinharvesting, but without the harvesting site complications. The techniquedisclosed here is referred to as a no-touch technique. This techniqueimproves endothelial integrity while reducing injury to the blood vessel(vein). It has also been found that this technique delays arterialatherosclerotic processes, conserves the vasa vasorum and it promotesthe nitric oxide synthase activity of endothelial cells.

According to one aspect, a vein harvesting assembly for harvesting avein in a body comprises: a dissecting member possessing a distal endportion and a proximal end portion, wherein the dissecting member isinsertable into the body and moved along a vein to dissect tissuesurrounding the vein; a covering member possessing a proximal endportion and a distal end portion, with the covering member possessing acovered space extending from the proximal end portion to the distal endportion, and the covering member being mountable on and movable alongthe dissecting member when the dissecting member is positioned in aliving body; and a cutting member comprised of an elongated member and ablade member so that rotation of the elongated member results in turningof the cutting member to cut tissue surrounding the vein, the cuttingmember being insertable into the space in the covering member and beingmovable in a distal direction along the space.

According to another aspect, a vein harvesting method for harvesting avein in a body comprises: inserting a dissecting member into a livingbody; forward moving the dissecting member along a vein in the body todissect tissue surrounding the vein; introducing a covering member intothe body and forward moving the covering member along the dissectingmember so that the dissecting member is positioned between the vein andthe covering member; withdrawing the dissecting member from the bodywhile the covering member remains in the body to create a space betweenthe covering member and the vein; introducing a cutting member into thebody and forward moving the cutting member to position the cuttingmember in the space; dissecting the vein using the cutting member;removing the covering member and the cutting member from the body afterthe vein is severed; and removing the severed vein from the body.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a blood vessel dissecting device according to afirst embodiment of the present disclosure.

FIGS. 2A and 2B illustrate a dissecting device forming a part of theblood vessel dissecting device shown in FIG. 1, wherein FIG. 2A is alongitudinal cross-sectional view and FIG. 2B is a transversecross-sectional view taken along the section line 2B-2B of FIG. 2A.

FIGS. 3A and 3B illustrate a cutting device forming a part of the bloodvessel dissecting device shown in FIG. 1, wherein FIG. 3A is a plan viewand FIG. 3B is a cross-sectional view taken along the section line 3B-3Bof FIG. 3A.

FIGS. 4A and 4B show views explaining a blood vessel dissecting methodcarried out using the blood vessel dissecting device shown in FIG. 1.

FIGS. 5A and 5B show views explaining the blood vessel dissecting methodcarried out using the blood vessel dissecting device shown in FIG. 1.

FIG. 6 is a perspective view of a dissecting device according to anotherembodiment.

FIG. 7A is a side view of the dissecting member forming a part of thedissecting device illustrated in FIG. 6.

FIG. 7B is a front view of the dissecting member forming a part of thedissecting device illustrated in FIG. 6.

FIG. 7C is a front perspective view of the dissecting member forming apart of the dissecting device illustrated in FIG. 6.

FIG. 7D is a bottom view of the dissecting member forming a part of thedissecting device illustrated in FIG. 6.

FIG. 8A is a front view of the dissecting member forming a part of thedissecting device illustrated in FIG. 6 illustrating the positioning ofthe projections relative to the bottom surface of the dissecting member.

FIG. 8B is a front view of another embodiment of the dissecting memberforming a part of the dissecting device illustrated in FIG. 6.

FIG. 9 is a front view of the dissecting member shown in FIG. 8A showingthe way in which the dissecting member interacts with the vein and aside branch of the vein during use of the dissecting device.

FIGS. 10A-10C are bottom perspective views of different embodiments ofthe dissecting member each possessing differently configuredprojections.

FIG. 11A is an enlarged side view of the dissecting member illustratingthe relative positions of different parts of the dissecting member.

FIG. 11B is an enlarged side view of the dissecting member illustratingthe relative positions of different parts of the dissecting member.

FIG. 12 is an enlarged side view of the dissecting member illustratingthe manner in which the dissecting member dissects the vein during useof the dissecting device.

FIGS. 13-15 depict a bottom perspective view, a bottom view and a frontview respectively of the dissecting member illustrating the framebordering the window of the upturned distal end portion of thedissecting member.

FIG. 16A is a front view of the dissecting member illustrating the wayin which the dissecting member, by virtue of the window, interacts withthe vein being dissected.

FIG. 16B is a front view of a manner of interaction between a dissectingmember without a window and a vein being dissected.

FIG. 17A is a front view of the dissecting member illustrating the wayin which the dissecting member and viewing member, by virtue of thewindow, interacts with the vein being dissected.

FIG. 17B is a front view of a dissecting member without a windowillustrating the way in which the dissecting member and the viewingmember interact with the vein being dissected.

FIGS. 18A and 18B are perspective and exploded views respectively ofanother embodiment of the dissecting device.

FIG. 19 is a side view of the dissecting member forming a part of thedissecting device shown in FIG. 18.

FIG. 20 is a front view of the dissecting member forming a part of thedissecting device shown in FIG. 18.

FIG. 21 is a front view of the dissecting member forming a part of thedissecting device shown in FIG. 18 illustrating the way in which thedissecting member interacts with the vein being dissected.

FIGS. 22a and 22B are perspective and exploded views respectively ofanother embodiment of the dissecting device.

FIG. 23 is a side view of a part of the dissecting device shown in FIG.22.

FIG. 24 is a front perspective view of a part of the dissecting deviceshown in FIG. 22.

FIG. 25 is a front view of the dissecting member forming a part of thedissecting device shown in FIG. 22 illustrating the way in which thedissecting member interacts with the vein being dissected.

FIG. 26 is a side view of a part of the dissecting device shown in FIG.22 illustrating the way in which the dissecting member interacts with aside branch of a vein being dissected.

FIGS. 27A and 27B are perspective and exploded views of anotherembodiment of the dissecting device.

FIG. 28 is a perspective view of the dissecting device shown in FIG. 27.

FIG. 29 is a transverse cross-sectional view of the dissecting deviceshown in FIG. 27.

FIG. 30 is a top perspective view of another embodiment of thedissecting device.

FIG. 31A is a perspective view of a part of the dissecting memberforming a part of the dissecting device illustrated in FIG. 30.

FIG. 31B is a cross-sectional view of the dissecting member forming apart of the dissecting device illustrated in FIG. 30.

FIG. 32A is a perspective view of a part of the covering member forminga part of the dissecting device illustrated in FIG. 30.

FIG. 32B is a cross-sectional view of the covering member forming a partof the dissecting device illustrated in FIG. 30.

FIG. 33A is a perspective view of a part of the dissecting member andcovering member forming a part of the dissecting device illustrated inFIG. 30.

FIG. 33B is a cross-sectional view of the dissecting member and coveringmember forming a part of the dissecting device illustrated in FIG. 30.

FIG. 33C is a perspective view of the dissecting member and coveringmember forming a part of the dissecting device illustrated in FIG. 30.

FIG. 34 is a perspective view of the covering member and the cuttingmember forming a part of the dissecting device illustrated in FIG. 30.

FIG. 35 is a perspective view of the covering member and the cuttingmember, with a viewing forming a part of the dissecting deviceillustrated in FIG. 30.

FIG. 36 is a cross-sectional view of the covering member and the cuttingmember forming a part of the dissecting device illustrated in FIG. 30.

FIG. 37 is a top perspective view of another embodiment of thedissecting device.

FIG. 38 is a bottom perspective view of the dissecting member forming apart of the dissecting device shown in FIG. 37 illustrating the viewingdevice positioned in the underside lumen.

FIG. 39 is a bottom perspective view of the dissecting member forming apart of the dissecting device shown in FIG. 37 illustrating the field ofview of the viewing device positioned in the underside lumen.

FIGS. 40-42 are top perspective views of another embodiment of thecovering member used in the disclosed dissecting devices.

FIG. 43 is a perspective view of another embodiment of the cuttingmember used in the disclosed dissecting devices.

FIG. 44 is a schematic side view of the cutting member shown in FIG. 43.

FIG. 45 is an illustration of another embodiment of the cutting memberused in the disclosed dissecting devices.

DETAILED DESCRIPTION

Examples of a blood vessel dissecting device and a blood vesseldissecting method disclosed here will be described in detail below,referring to the attached drawings.

FIGS. 1-5B illustrate a blood vessel dissecting device and blood vesseldissecting method carried out using the blood vessel dissecting deviceaccording to a first embodiment representing one example of the veindissecting device and method disclosed here. In the followingdescription, for convenience of explanation, the right side in FIG. 1 isreferred to as the “distal” side or end, and the left side in the figureis referred to as the “proximal” side or end.

A blood vessel (vein) dissecting device 100 shown in FIG. 1 is a deviceused to dissect or harvest a blood vessel for use as a bypass vessel incarrying out blood vessel bypass grafting (particularly, coronary arterybypass grafting: CABG). Using this blood vessel dissecting device 100, ablood vessel can be harvested in the state of being covered with thesurrounding tissue (fat, connective tissue, etc.), preferably to theextent that the blood vessel is not exposed to the surface of thesurrounding tissue and the blood vessel does not have the lateralsurface that is exposed to the external atmosphere. More preferably, tothe extent that an outer surface of the blood vessel is not exposed tothe surface of the surrounding tissue and the outer surface of the bloodvessel does not have the lateral surface that is exposed to the externalatmosphere. The blood vessel to be harvested using the blood vesseldissecting device 100 is not particularly limited insofar as it is ablood vessel that can be used as a bypass vessel. Examples of theapplicable blood vessel include internal thoracic artery, gastroepiploicartery, radial artery, and great saphenous vein.

It is preferable, however, that the blood vessel to be harvested is thegreat saphenous vein. The blood vessel dissecting device 100 and methoddisclosed here facilitate harvesting or dissecting a blood vessel in thestate in which the blood vessel is covered with the surrounding tissue.Harvesting the great saphenous vein using the blood vessel dissectingdevice 100 and method disclosed here, and using the harvested ordissected vein as a bypass vessel enhances long-term patency rate afterthe bypass grafting operation. In view of this, in the following,examples of harvesting or dissecting a great saphenous vein by use ofthe blood vessel dissecting device 100 and method disclosed here will bedescribed as representative of a blood vessel to which the device andmethod disclosed here are applicable.

As shown in FIG. 1, the blood vessel dissecting device 100 includes orpossesses a dissecting device 200 and a cutting device 300. Both thedissecting device 200 and the cutting device 300 are devices which areinserted into a living body along the great saphenous vein. Thedissecting device 200 and the cutting device 300 will now be describedin detail below. The dissecting device 200 and the cutting device 300may be used in other than a living body. For example, the dissectingdevice 200 and the cutting device 300 can be used with other bodies suchas a cadaver and a simulator intended to simulate the living body.

The dissecting device 200 has an elongated bar-like shape (bar-shaped)extending substantially straight, and is provided at its distal end witha dissecting section 220 for dissecting tissue. In addition, as shown inFIG. 2B, the dissecting device 200 has a flat shape (flattened shape asseen in vertical cross-section to a central axial direction of thedissecting device) in section. The cross-sectional shape of thedissecting device 200 is not specifically restricted; for example, thecross-sectional shape may be a crushed-circle-like shape (flattenedcircular shape), such as an oblong and an ellipse, a rectangle roundedat corners, or the like.

The width (the length in the major axis direction of the cross-sectionalshape) W1 of the dissecting device 200 is greater than the outsidediameter of the blood vessel to be harvested (in this embodiment, thegreat saphenous vein). To be more specific, the width W1 is preferablyabout 4 mm to 2 cm greater than the outside diameter of the blood vesselto be harvested. This helps ensure that the possibility of contactbetween the cutting device 300 and the great saphenous vein can beeffectively lowered at the time of inserting the cutting device 300 intothe living body along the dissecting device 200, as will be explained inthe “blood vessel harvesting method” described later.

In addition, the dissecting device 200 is provided, at both ends of themajor axis of the cross-sectional shape thereof, with rails 231 and 232in the form of linear stretches of recess (or trenches/grooves) whichextend in the axial direction of the dissecting device 200. Each of therails 231 and 232 is used for connection of the dissecting device 200with the cutting device 300, and functions as a guide section forguiding the cutting device 300. Note that the rails 231 and 232 are notlimited to the linear stretches of recess (or trenches/grooves) but maybe, for example, linear stretches of projection (or ridges or ribs),insofar as they each enable connection of the dissecting device 200 withthe cutting device 300.

As shown in FIG. 2A, the dissecting device 200 is provided with aninsertion hole 210 which opens at the proximal end and extends to adistal portion (the dissecting section 220). In this illustratedembodiment, the insertion hole 210 is a blind hole, meaning theinsertion hole 210 is closed at its distal end. Into the insertion hole210 is inserted an imaging device 400. The imaging device 400 is notspecifically restricted. For example, the imaging device 400 in thisembodiment, as depicted in FIG. 2A, includes or possesses an elongatedmain body section 410, and an illuminating section (not shown) foremitting illumination light and an imaging section 430 for imaging thefront side of the dissecting device 200. The illuminating section andthe imaging section 430 are disposed at a distal portion of the mainbody section 410. The imaging section 430 includes or possesses, forexample, an objective lens system disposed at the distal portion of themain body section 410 and an imaging element (e.g., solid state imagesensor such as CMOS image sensor or CCD sensor) disposed opposite to theobjective lens system.

The dissecting section 220 is tapered in a narrowing manner toward thedistal end of the dissecting device 200. More specifically, the distalend portion of the dissecting section 220 possesses a tapered roughlyconical shape so that the length in the minor axis direction and thelength in the major axis direction of the cross-sectional shape of thedissecting section 220 are both gradually decreased in a directiontoward the distal end. Such a dissecting section 220 is blunt in thethickness direction, and has such a degree of sharpness (bluntness) asto be able to dissect tissues having different properties (for example,fat and skin, fat and fascia, fat and blood vessel, fat and bone, etc.)from each other without cutting branch vessels branched from the greatsaphenous vein. This helps ensure that a dissecting function can besufficiently exhibited and the branch vessels are restrained from beingdamaged or cut by the dissecting section 220. Accordingly, bleeding canbe suppressed, and the intended technique can be performed safely andsmoothly. Note that the shape of the dissecting section 220 is notparticularly limited insofar as it enables dissection of tissues in thethickness direction (minor axis direction) of the tissues. For example,the dissecting section 220 may be in the shape of a duck-bill such thatthe length in the minor axis direction of the cross-sectional shape ofthe dissecting section 220 is gradually decreased (tapered) toward thedistal end and the cross-sectional shape at the distal end is a linesegment along the major axis direction.

The dissecting section 220 is substantially colorless and transparentand is light-transmitting. This helps ensure that when the imagingdevice 400 is inserted into the insertion hole 210, the front side ofthe dissecting device 200 can be observed through the dissecting section220 by the imaging device 400. In other words, the dissecting section220 has the function as an observation section for observation of theinside of the living body (the great saphenous vein and itssurroundings), in addition to the aforementioned function as thedissecting section. Note that the dissecting section 220 is not limitedto the colorless transparent property but may be colored in red, blue,green or the like, insofar as it is light-transmitting.

The cutting device 300, at the time of moving along a great saphenousvein 1000, cuts the fat (inclusive of connective tissue) surrounding thegreat saphenous vein 1000 and, in addition, cuts and stanches the branchvessels branched from the great saphenous vein 1000.

The cutting device 300 is elongated plate-like in shape (plate-shaped).As shown in FIGS. 1 and 3A, the cutting device 300 has a groove portion320 opening in a distal portion of the cutting device. The grooveportion 320 possesses: a tapered blood vessel guide groove section(first groove section) 321 having a width gradually decreasing towardthe proximal side; and a straight blood vessel treating groove section(second groove section) 322 which is located on the proximal side of theblood vessel guide groove section 321 and is substantially constant inwidth. The blood vessel guide groove section 321 is a groove section forguiding a branch vessel into the blood vessel treating groove section322 at the time of pushing the cutting device 300 forward in a livingbody, and is tapered in shape for the guiding to be smoothly achieved.On the other hand, the blood vessel treating groove section 322 is agroove section for cutting and stanching the branch vessel guided to theblood vessel treating groove section 322 by the blood vessel guidegroove section 321. Further, the blood vessel treating groove section322 is provided with a treating section 330 for cutting and stanching abranch vessel.

As shown in FIG. 3A, the treating section 330 has a bipolar structureincluding a pair of electrodes 331 and 332 configured to generate anelectric field inside the blood vessel treating groove section 322. Theelectrode 331 is disposed at a proximal end portion of the blood vesseltreating groove section 322, while the electrode 332 is disposed on bothsides with respect to the width direction of the blood vessel treatinggroove section 322. With a high-frequency AC voltage impressed betweenthe electrodes 331 and 332, it is possible to heat and cut a branchvessel 1100 guided into the blood vessel treating groove section 322 andto stanch the blood vessel through thermal coagulation. A distal portion(a portion exposed to the blood vessel treating groove section 322) 331a of the electrode 331 is preferably so sharp as to be able to cut thebranch vessel 1100. This helps ensure that if thermal coagulation(stanching) of the branch vessel 1100 can at least be achieved by theelectric field generated between the electrodes 331 and 332, the branchvessel 1100 can be physically cut by the distal portion 331 a of theelectrode 331. Accordingly, the assuredness of the treatment by thetreating section 330 is enhanced.

The width W2 of the blood vessel treating groove section 322 is notparticularly limited but it is preferably narrower than the outsidediameter of the branch vessel 1100. This helps ensure that the branchvessel 1100 can be pressed flat inside the blood vessel treating groovesection 322 as shown in FIG. 3A, and, consequently, the treatment(cutting and stanching) at the treating section 330 can be performedmore reliably.

The cutting device 300 is provided with a cutting edge section (cuttingsection) 350 for cutting the fat surrounding the great saphenous vein1000. The cutting edge section 350 is disposed at a distal portion ofthe cutting device 300; in this embodiment, it is disposed along theblood vessel guide groove section 321. As will be explained also in the“blood vessel harvesting method” described later, the cutting edgesection 350 has the function of cutting the fat surrounding the greatsaphenous vein 1000 at the time of pushing the cutting device 300forward in the living body. Such a cutting edge section 350 preferablyhas such a sharpness as to be able to cut the fat without cutting thebranch vessel 1100. This helps ensure that cutting of the branch vessel1100 by the cutting edge section 350 is inhibited, so that bleeding isrestrained, and the intended technique can be performed safely andsmoothly.

As shown in FIG. 3B, the cutting device 300 has a pair of protectionsections 341 and 342 provided on both sides with respect to the cuttingdevice's width direction (the direction orthogonal to its movingdirection). The protection sections 341 and 342 each extend along theaxial direction of the cutting device 300, and their peripheral surfaces(side surfaces and distal surfaces) are rounded. As will be explainedalso in the “blood vessel harvesting method” described later, theprotection section 341 moves along and between fat and skin whiledissecting them from each other, at the time of pushing the cuttingdevice 300 toward the distal side in a living body. Since the fat andthe skin having different properties, they are rather easy to dissectfrom each other, even though a distal end portion of the protectionsection 341 is rounded, and the dissecting function of dissecting thefat and the skin from each other can be exhibited sufficiently. Inaddition, the rounding helps ensure that a branch vessel can berestrained from being damaged or cut by the protection section 341, and,further, damage to (cauterization of) the skin due to sliding against(friction with) the protection section 341 can be restrained. Similarly,the protection section 342 moves along and between the fat and thefascia while dissecting them from each other at the time of pushing thecutting device 300 toward the distal side in the living body. Since thefat and the fascia having different properties, they are easy to dissectfrom each other, even though a distal end portion of the protectionsection 342 is rounded, and the dissecting function of dissecting thefat and the fascia from each other can be exhibited sufficiently.Besides, the rounding helps ensure that the branch vessel can berestrained from being damaged or cut by the protection section 342, and,further, damage to (cauterization of) the fascia due to sliding against(friction with) the protection section 342 can be restrained.

As shown in FIGS. 3A and 3B, the cutting device 300 has connectionsections 381, 382, 383 and 384 configured to connect with the rails 231and 232 of the dissecting device 200. The connection sections 381 and382 are provided at the protection section 341, and disposed on mutuallyopposite surface sides. Similarly, the connection sections 383 and 384are provided at the protection section 342, and disposed on mutuallyopposite surface sides. These connection sections 381 to 384 arecomposed of stretches (lengths) of projection (or ridges or ribs) whichextend in the axial direction of the cutting device 300 and correspondto the stretches of recess (trenches) of the rails 231 and 232. Sincesuch connection sections 381 to 384 are provided, unintended detachmentof the dissecting device 200 and the cutting device 300 from each otheris prevented, so that the intended technique can be carried out moresmoothly and accurately. Thus, in this example of the blood vesseldissecting device, both the cutting device 300 and the dissecting device200 possess connection structure configured to connect the cuttingdevice 300 and the dissecting device 200 to each other.

A method of harvesting or dissecting a blood vessel by use of the bloodvessel dissecting device 100 possesses: a first step (blood vesseldissecting method) of dissecting the great saphenous vein 1000 in thestate of being covered with surrounding fat 1200 by use of the bloodvessel dissecting device 100; a second step of ligating the greatsaphenous vein 1000 and then cutting the great saphenous vein 1000; anda third step of extracting the great saphenous vein 1000 in the state ofbeing covered with the surrounding fat 1200 from the living body.

First, the position of the great saphenous vein 1000 to be harvested isconfirmed, and skin is incised on the basis of the position of the greatsaphenous vein. Next, the dissecting device 200 with the imaging device400 inserted in the dissecting device 200 is prepared, and, whileobserving the inside of the living body by the imaging device 400, thedissecting device 200 is inserted from the incision 1300 into the livingbody along the great saphenous vein 1000 while keeping the dissectingdevice 200 spaced from the great saphenous vein 1000. Then, as shown inFIG. 4A, the dissecting device 200 is disposed on the upper side (theskin 1400 side) of the great saphenous vein 1000. In this case, thedissecting device 200 is so disposed that the thickness direction of thedissecting device 200 agrees substantially with the aligning directionin which the dissecting device 200 and the great saphenous vein 1000 arealigned. In this operation, the dissecting device 200 is insertedbetween the fat 1200 and the skin 1400 (between the tissues havingdifferent properties), and the skin 1400 and the fat 1200 are dissectedfrom each other in the thickness direction of the dissecting device 200(in the aligning direction in which the dissecting device 200 and thegreat saphenous vein 1000 are aligned). Such an area is an area wheredissection can be achieved particularly easily, so that this operationcan be carried out more smoothly and accurately. The dissecting device200 thus dissects tissue in a direction along the longitudinal extent ofthe vein.

Subsequently, the cutting device 300 is prepared, and the connectionsection 381 is connected to the rail 231 of the dissecting device 200.Then, the state of the dissecting device 200 is aligned on the upperside of the great saphenous vein 1000, the cutting device 300 isinserted into and moved in the living body while guiding the cuttingdevice 300 with the dissecting device 200 as shown in FIG. 4B. In thiscase, the cutting device 300 is moved forward while dissecting the skin1400 from the fat 1200 by the protection section 341, and whiledissecting the fascia 1500 from the fat 1200 by the protection section342. Furthermore, the cutting device 300 cuts the fat 1200 present onthe one lateral side of the great saphenous vein 1000 by the cuttingedge section 350 in the left-right direction (in the aligning directionin which the cutting device 300 and the great saphenous vein 1000 arealigned), and, concurrently, cuts and stanches the branch vessel 1100 bythe treating section 330.

Here, since the width W1 of the dissecting device 200 is greater thanthe outside diameter of the great saphenous vein 1000 as aforementioned,the cutting device 300 can be pushed forward along the great saphenousvein 1000 while keeping the cutting device 300 laterally spaced from thegreat saphenous vein 1000, as shown in FIG. 4B, so that the greatsaphenous vein 1000 can be prevented from being damaged during thisoperation. In addition, since the protection sections 341 and 342 arerounded, the possibility of damaging the skin 1400 or the fascia 1500 bycontact with the cutting device 300 is lowered.

Next, the cutting device 300 is drawn out, and the connection section382 of the cutting device 300 thus drawn out is connected to the rail232 of the dissecting device 200. Then, the cutting device 300 isinserted again into the living body while guiding the cutting device 300with the dissecting device 200, to dispose the cutting device 300 on theother lateral side of the great saphenous vein 1000, as shown in FIG.5A.

Subsequently, the dissecting device 200 is drawn out, and the rail 232of the dissecting device 200 thus drawn out is connected to theconnection section 384 of the cutting device 300. Then, the dissectingdevice 200 is inserted again into the living body while guiding thedissecting device 200 with the cutting device 300, to dispose thedissecting device 200 on the lower side (the fascia 1500 side (boneside)) of the great saphenous vein 1000, as shown in FIG. 5B. In thisoperation, the dissecting device 200 is inserted between the fat 1200and the fascia 1500 (inserted into the boundary between the tissueshaving different properties), and the fat 1200 and the fascia 1500 aredissected from each other in the thickness direction of the dissectingdevice 200. Such an area is an area where dissection can be particularlyeasily achieved, so that this operation can be carried out more smoothlyand accurately.

By the above-mentioned operations, the fat 1200 surrounding the greatsaphenous vein 1000 is dissected over the entire perimeter of the vein,and the great saphenous vein 1000 is dissected in the state of beingcovered with the surrounding fat 1200. The thickness of the fat 1200dissected together with the great saphenous vein 1000 and located in thesurroundings of the great saphenous vein 1000 is not particularlylimited. It is preferable, however, that the thickness is about 0.1 mmto 10 mm, more preferably about 1 mm to 8 mm, and further preferablyabout 3 mm to 5 mm.

Next, both ends of that part of the great saphenous vein 1000 which isto be harvested are ligated and then cut.

Subsequently, the great saphenous vein 1000 is extracted in the state ofbeing covered with the surrounding fat 1200, to the outside of theliving body via the incision 1300.

By the first to third steps as above-mentioned, the great saphenous vein1000 can be harvested while the great saphenous vein is in the state ofbeing covered with the surrounding fat 1200. In such a method, whileusing the dissecting device 200 for treating a part which is rather easyto dissect so as to reduce such damages as bleeding and while using thecutting device 300 for treating the fat which is difficult to dissect,the great saphenous vein 1000 can be harvested smoothly and with lowinvasion. In addition, since the first step can be carried out withoutcutting the great saphenous vein 1000, blood can be kept flowing throughthe great saphenous vein 1000 for a time as long as possible.Accordingly, the great saphenous vein 1000 is placed in an ischemicstate for a shortened period of time, so that the great saphenous vein1000 can be harvested with less damage.

Here, a great saphenous vein 1000 covered with fat 1200 constitutes abypass vessel having a superior long-term patency rate, as compared witha great saphenous vein 1000 not covered with fat 1200. The reason isconsidered as follows. While the great saphenous vein 1000 is used as anartery bypass vessel, arteries are generally higher than veins in theblood pressure (the internal pressure exerted thereon by blood). When agreat saphenous vein in an exposed state of being not covered withtissue is used as a bypass vessel, therefore, the great saphenous veincannot endure the blood pressure and is therefore expanded by the bloodpressure, resulting in lowered blood flow. In addition, thickening ofblood vessel wall occurs in the process of remodeling (structuralalteration) or in the process of recovery from damage to tissue. Suchthickening of blood vessel wall is considered to influence thedevelopment of arterial sclerosis. From such a cause, the use of a greatsaphenous vein in the exposed state of being not covered with tissue asa bypass vessel would, in the long run, lead to vascular occlusion.

On the other hand, where the great saphenous vein 1000 is covered withfat 1200, expansion of the great saphenous vein 1000 is restrained bythe fat 1200, and bending and the like of the great saphenous vein 1000are also restrained. Therefore, the lowering in blood flow asabove-mentioned can be inhibited. In addition, the covering with the fat1200 reduces damages to the great saphenous vein 1000, specifically,damages to endotheliocytes, smooth muscles, nutrient vessels (capillaryplexus), etc. Therefore, the aforementioned thickening of blood vesselwalls can be restrained. For these reasons, the use of the greatsaphenous vein 1000 covered with the fat 1200 as a bypass vessel enablesan excellent long-term patency rate. Especially, in this embodiment,nutrient vessels are left at the blood vessel walls of the greatsaphenous vein 1000 and in the fat 1200. For this reason, nutrients aresupplied to the great saphenous vein 1000 serving as the bypass vessel,even after the bypass grafting. This is considered to be the reason whythe aforementioned effect is enhanced.

While this embodiment has been described, the configuration of the bloodvessel dissecting device 100 is not limited to the configuration in thisembodiment. For example, the rails 231 and 232 may be omitted from thedissecting device 200, and the connection sections 381 to 384 may beomitted from the cutting device 300. In this case, for example, it maybe sufficient to insert the cutting device 300 into a living body alongthe dissecting device 200 which is inserted into the living bodyearlier. Alternatively, it may be sufficient to insert the dissectingdevice 200 into a living body along the cutting device 300 which isinserted into the living body earlier.

The cutting device 300 is not specifically restricted insofar as it cancut the fat 1200. For instance, a configuration may be adopted in whichthe fat 1200 is cut by something like a pair of scissors.

The blood vessel dissecting method is not limited to the procedureadopted in this embodiment. For instance, the order of insertion of thedissecting device 200 and the cutting device 300 is not specificallyrestricted, and any of left, right, upper and lower portions of thegreat saphenous vein 1000 may be dissected first. For instance, aprocedure may be adopted in which, first, upper and lower sides of thegreat saphenous vein 1000 are dissected by use of the dissecting device200, and, then, left and right sides of the great saphenous vein 1000are dissected by use of the cutting device 300. On the other hand, leftand right sides of the great saphenous vein 1000 may first be dissectedby use of the cutting device 300, and, then, upper and lower sides ofthe great saphenous vein 1000 may be dissected by use of the dissectingdevice 200.

While one dissecting device 200 and one cutting device 300 are used inthis embodiment, two dissecting devices 200 and two cutting devices 300may be used. In this case, for example, a procedure may be adoptedwherein, first, a first dissecting device 200 is disposed on the upperside of the great saphenous vein 1000, next a first cutting device 300is disposed on one of left and right sides of the great saphenous vein1000, then a second cutting device 300 is disposed on the other of theleft and right sides of the great saphenous vein 1000, and a seconddissecting device 200 is disposed on the lower side of the greatsaphenous vein 1000. Such a procedure eliminates the need to draw outthe dissecting device 200 and the cutting device 300 in the course ofthe procedure, so that the aforementioned procedure can be carried outsmoothly.

While the dissecting device 200 is inserted between the fat 1200 and theskin 1400 and between the fat 1200 and the fascia 1500 in thisembodiment, the insertion position of the dissecting device 200 is notparticularly limited. For instance, the dissecting device 200 may beinserted between tissues having different properties, such as betweenthe fat 1200 and a blood vessel (other than the great saphenous vein1000), between the fat 1200 and a bone, between the fascia 1500 and abone, or the like. Further, the insertion between tissues havingdifferent properties (insertion into the boundary between tissues havingdifferent properties, insertion into tissue between tissues havingdifferent properties, or the like) is not restrictive; for example, thedissecting device 200 may be inserted into the fat 1200, therebydissecting the fat 1200.

While fat is cut by the cutting device 300 in this embodiment, thetissue to be cut by the cutting device 300 is not limited to fat. Forinstance, tissue between a skin-fat boundary and a fat-muscle boundary,tissue between a skin-fat boundary and a fat-interosseous membraneboundary, connective tissue, tissue between a skin layer and a musclelayer, tissue between a skin layer and an interosseous membrane, branchvessels, and the like may also be cut by the cutting device 300.

In this embodiment, the dissecting device 200 is disposed spaced fromthe great saphenous vein 1000 so as not to contact the great saphenousvein 1000. But the dissecting device 200 may be disposed in contact withthe great saphenous vein 1000. In other words, the dissecting device 200may be inserted between the great saphenous vein 1000 and the fat 1200.

FIG. 6 illustrates another embodiment of a vein dissecting or harvestingdevice. This embodiment of the vein dissecting device 500 includes orpossesses a dissecting member 508 which incorporates a cutting member518. The vein dissecting device 500 also includes or possesses anelongated hollow member 502 projecting rearwardly (in the proximaldirection) from the dissecting member 508. The elongated hollow member502 possesses a proximal end portion 504 and a distal end portion 506,and the dissecting member 508 is mounted on or fixed to the distal endportion 506 of the elongated hollow member 502.

FIGS. 7A-7D depict the dissecting member 508 in more detail. Thosefigures illustrate that the dissecting member 508 possesses a mount 512that may be generally tubular in configuration. By way of this mount512, the dissecting member 508 is mounted on the distal end portion 506of the elongated hollow member 502. This can be accomplished by, forexample, welding, adhesive, fitting together, etc. Projecting from themount 512 are two spaced-apart side portions or side walls 514. In theillustrated embodiment, these side portions 514 project verticallydownwardly away from the mount 512 as best illustrated in FIG. 7B. Thedissecting member 508 also includes or possesses holding portions 520,each of which projects inwardly from one of the side portions 514. Inthe illustrated embodiment, the holding portions 520 are horizontallyoriented and project inwardly towards one another as generallyillustrated in FIG. 7B. The holding portions 520 are preferablyconfigured and arranged to retain dissected tissue and/or the vein.

The mount 512 defines a top portion which, together with the twospaced-apart side portions 514 and the two holding portions 520, definesa space or region 513. As described in more detail below, this region513 represents a vein-receiving region or space configured to receivethe vein (e.g., saphenous vein) during use and operation of thedissecting device 500. An example of this is shown in FIG. 9 whichschematically illustrates the dissecting member 508 during use. As thedissecting member 508 is moved along the vein 1000 during use, the vein1000 is received or positioned in the vein-receiving region or space 513defined between the holding portions 520, the side portions or sidemembers 514 and a part of the mount 512 forming an upper confine.

As best illustrated in FIGS. 7A and 7C, the distal end portion 510 ofthe dissecting member 508 is configured as an upturned member. Accordingto one embodiment as illustrated, the upturned member 510 may be in theform of an upwardly curved member that is curved along at least itsdistal end portion of its extent in an upward direction. The upturneddistal end portion 510 of the dissecting member 508 constitutes anupwardly curved protrusion member. FIG. 11 shows that the upturned orcurved distal end portion 510 of the dissecting member 508 can beconfigured to possess the distal end portion that is upwardly curved anda proximal portion 517 that is linear or straight. As will be explainedin more detail below, the upturned or upwardly curved distal end portion510 is configured to curve away from the vein during use of thedissecting device 500. The upturned or upwardly curved distal endportion 510 is preferably made of transparent material. This can helpfacilitate viewing a position of the vein with a viewing device andfacilitate moving the viewing device along the vein.

Each of the side members 514 includes or possesses a groove 516 that isopen at one end (i.e., the forward or distal end on the left asillustrated in FIG. 7A) and closed at the opposite end. At the closedend, the groove terminates in a curved section representing a cuttingmember 518. The grooves 516 and the cutting members 518 are preferableconfigured in a way that facilitates cutting of, for example, sidebranches of the vein. That is, side branches projecting from the vein,such as the side branches 1100 shown in FIGS. 4A, 4B, 5A and 5B, can becaptured and guided in the grooves 516 and cut by the cutting member518. To facilitate cutting, the cutting members 518 can be sharpened orotherwise provided with a cutting edge.

The dissecting member 508 also possesses several projections 522. Eachprojection 522 is positioned at the front surface or front side of oneof the side portions 514, generally at a position where each sideportion 514 intersects the respective holding portion 520 as bestillustrated in FIG. 7B.

The projections 522 help facilitate smooth insertion of the dissectingdevice 508 into the living body and relatively smooth movement of thedissecting device along the vein (e.g., saphenous vein) during thedissecting operation. As described in more detail below, the method ofuse or operation can involve initially contacting the distal end portionof the dissecting member and the projections 522 of the dissectingmember on a living body while the dissecting device is inclined to thebody, and then inserting the distal end portion of the dissecting memberinto the body after puncturing or sticking the body with the projectionand inserting the projection into the living body.

The projections 522 are preferably positioned so that they are locatedsuperior to (i.e., vertically above) the bottom surface of thedissecting device (e.g., the bottom surface of the holding portions520). The projections 522 are preferably located superior to the bottomsurface of the dissecting device in FIG. 8B.

In the embodiment of the dissecting member 508 illustrated in FIGS.7A-7D and FIG. 8A, the side portions or side members 514 are straightvertically oriented members, the holding portions 520 are straighthorizontally oriented members, and the holding portions 520 areperpendicular to the respective side portions 514. The dissecting member508 is not limited to this particular configuration. FIG. 8B shows analternative configuration of the dissecting member in which the sideportions or side members 514′ are curved generally inwardly towards oneanother and the holding portions 520′ are curved generally inwardlytowards one another. It is also possible to implement otherconfigurations, such as one in which the side portions are straight andthe holding portions are curved, and another one in which the sideportions are curved and the holding portions are straight.

The dissecting member 508 may be configured such that the mount 512, theside portions 514, the holding portions 520, the projections 522 and theupturned distal end portion 510 are formed as an integrated and unitarypart.

The embodiment of the dissecting member 508 shown in FIGS. 7A-7Dincludes or possesses projections 522 in the form of spherical memberspositioned at the intersection of the side portion and the holdingportion. The projections are not limited to this configuration andpositioning. FIGS. 10A-10C illustrate several other embodiments of theprojections. In these different embodiments, the projections aredifferently configured and arranged relative to the version shown inFIGS. 7A-7D. In FIG. 10A, the projections 522′ are configured ascone-shaped or bullet-shaped projections at the corner where the sideportion 514 meets or intersects the holding portion 520. The projection522″ in FIG. 10B is formed by a tapering part of the holding portion 520at which the front edge of the holding portion tapers to a rounded pointat the midpoint of the holding portion 520. The embodiment of theprojection 522′″ in FIG. 100 is similar to FIG. 10B, but additionallyincludes or possesses the spherically shaped projection at the taperedmidpoint of the holding portions. The pointed nature of the projectionsshown in FIGS. 10 A and 10B facilitate dissecting and sticking thetissue.

As generally illustrated in FIG. 11, it is preferable that theprojections 522 be positioned so that the entirety of the groove 516 ineach of the side portions 514 is located posterior to the projection 522(i.e., behind, proximal to or to the right of the projection 522 in FIG.11). Stated differently, the projection 522 on each of the side portionsor side members 514 is positioned in front of or on the distal side ofthe groove 516 (i.e., to the left of the groove in FIG. 11). The groove516 on each of the side portions 514 is also preferably locatedposterior to (i.e., below) the upturned distal end portion 510 of thedissecting member 508 as also illustrated in FIG. 11. The groove 516 ineach of the side portions 514 is positioned superior to or above theprojections 522 as also depicted in FIG. 11A. FIG. 11A also shows thatthe projections 522 are positioned posterior to (i.e., behind orproximal to) the upturned distal end portion 510 of the dissectingmember 508. The projections 522 on each of the side portions 514 arealso located under or below the bottom surface 511 of the upturneddistal end portion 510.

A method of using the dissecting device 500 shown in FIGS. 6, 7A-7D, 8Aand 8B to harvest or dissect a blood vessel (e.g., a vein such as asaphenous vein) may be generally similar to the method described above.That is, the method may involve using the dissecting device 500 todissect the blood vessel in a condition in which the blood vessel iscovered with surrounding fat (e.g., some of the fat 1200 shown in FIGS.4A, 4B, 5A and 5B), ligating and cutting the blood vessel, and thenremoving the severed or dissected blood vessel in a condition in whichthe blood vessel is covered with surrounding fat from the living body.More specifically, the position of the blood vessel to be dissected orharvested (e.g., great saphenous vein 1000 shown in FIGS. 4A, 4B, 5A and5B) to be harvested is identified or confirmed, and an incision is thenmade in the living body (e.g., leg of a patient) to provide an accesssite to the vein (saphenous vein) as well as the saphenous fasciasurrounding the vein. The living body is incised based on the confirmedor determined position of the blood vessel. Holding the elongated member502 of the dissecting device 500 (or another operating member connectedto the elongated member 502), the user may then insert the dissectingmember 508 of the dissecting device 500 into the living body by way ofthe incision. The dissecting member 508 is then manipulated or moved togenerally position the dissecting member 508 relative to the vein 1000in the manner illustrated in FIG. 9. In this position, the vein 1000 islocated in the region or area 513 surrounded by the holding portions520, the side portions 514 and the top portion defined by the mount 512.FIG. 9 illustrates the positioning of the dissecting member 508 from thefront (i.e., as viewed along the vein 1000).

FIG. 12 illustrates the dissecting member 508 from the side as thedissecting member 508 is moved along the vein 1000. FIG. 12 illustratesthat as the dissecting member 508 is moved along the vein 1000 in theforward or distal direction indicated by the arrow (i.e., to the left inFIG. 12) the upturned member 510 constituting the distal end portion ofthe dissecting member lifts and separates fat tissue 1200 from the vein1000. The fat tissue is peeled away in much the same way as an adhesivesticker is peeled off its backing. This peeling result is illustrated inFIG. 12. By virtue of the curved or upturned distal end portion 510 ofthe dissecting member 508, potentially damaging contact between thedistal end portion of the dissecting member and the vein 1000 isreduced. The curved or upturned member 510 thus advantageously helps toavoid injury to the vein 1000. If the distal end portion of thedissecting member was configured as a straight distal end portion (i.e.,no curved configuration), it would be more likely for the distal endportion of the dissecting member to contact the vein, for example byvirtue of the distal-most end of the dissecting member poking orsticking the vein. The upturned distal end portion 510 of the dissectingmember facilitates dissection or separation of the tissue from the vein.The upturned member possesses only a limited circumferential extent(i.e., the upturned distal end portion 510 does not extend 360°). Themethod of use or operation can thus involve forward moving thedissecting member for a relatively short distance, rotating thedissecting device to dissect a circumferential region, forward movingthe dissecting device so that the upturned member helps dissects adifferent circumferential region, forward moving the dissecting device,etc.

As the dissecting member 508 moves along the vein 1000, the dissectingdevice may encounter side branches of the vein 1000. Examples of suchside branches are shown in FIGS. 4A, 4B, 5A, 5B and identified as 1100.By appropriately aligning the side branch 1100 with the groove 516 inone of the side portions 514, the side branch may enter the groove 516as the dissecting member 508 is moved forward and will be cut by thecutting member 518.

After the dissecting member 508 is advanced along the entirelongitudinal extent of the vein 1000 that is to be dissected or removed,the dissecting member 508 is moved in the rearward or proximal direction(i.e., to the right in FIG. 12). The dissecting member 508 can then berotated, for example, by ninety (90) degrees, and then once againinserted into the living body to dissect the tissue surrounding the vein1000 (i.e., the fat 1200) from the vein 1000 at circumferential locationdifferent from the dissection performed by the first pass of thedissecting member 508 along the vein 1000. This procedure can berepeated as many times as necessary to dissect the tissue from the veinso that the vein (and tissue surrounding the vein) is separated fromadjacent tissue. It may be necessary to perform several passes of thedissecting member 508 as described. With the dissecting member 508preferably removed from the living body, the ends of the dissected veinare then ligated and cut, and the severed vein is then removed from theliving body.

To further facilitate the smooth introduction of the dissecting member508 into the living body and movement of the dissecting member 508 alongthe vein, the projections 522 are preferably positioned relative to theupturned or curved distal end portion 510 of the dissecting member 508so that the projections 522 are located posterior to (rearward of orproximal to) a tangent to the bottom surface of the upturned or curveddistal end portion 510 of the dissecting member 510 as illustrated inFIG. 11B. In the embodiment shown in FIG. 11B, the bottom surface of theupturned member 510 constituting the distal end portion of thedissecting member possesses a flat region 515, and the tangent line 523represents a continuation of this flat bottom surface portion 515 of theupturned member 510. The upturned member 510 is preferably configured sothat when the flat bottom surface portion 515 of the upturned member 510contacts a surface of the body, the projections 522 don't contact thesurface of the body. That is, when the flat bottom surface portion 515of the upturned member 510 contacts a surface of the body, the tangentline 523 is under the projections. If the bottom surface of the upturnedor curved distal end portion 510 of the dissecting member 508 is curvedalong its entire extent (i.e., there is no flat bottom surface portion515), the projections 522 are preferably positioned behind or proximalto a tangent line anywhere along the curved bottom surface.

One benefit associated with the above-described positioning of theprojections 522 relative to the tangent arises during insertion of thedissecting member into the living body. If the projections 522 arepositioned in front of the line or tangent 523, when the dissectingmember is inserted into the living body by way of the incision in theskin, the projections 522 may tend to contact (poke or stick) andpossibly damage the vein (tissue) before the upturned distal end portion510 of the dissecting member 508 has an opportunity to begin the desiredpeeling back of the tissue and vein dissection shown in FIG. 12. In sucha case, it may be difficult to change the direction of movement of thedissecting member 508 as is typically desired because the direction ofmovement of the dissecting device during insertion through the skinincision is different than the movement of the dissecting member alongthe vein during the dissection operation.

FIGS. 13-15 illustrate additional aspects of the upturned or upwardlycurved distal end portion 510 of the dissecting member 508. Asillustrated in FIGS. 13 and 14, the upturned or curved distal endportion 510 of the dissecting member 508 possesses a frame portion 524that surrounds a through opening or through hole defining a window 526.As illustrated in FIG. 14, as seen from the bottom, the frame portion524 exhibits a curvilinearly tapered shape (bullet shape). The benefitassociated with configuring the upturned or curved distal end portion510 of the dissecting member 508 as a frame portion surrounding thethrough window 526 is that there is less surface contact between thebottom surface of the upturned distal end portion 510 of the dissectingmember 508 and the tissue (fat) as the dissecting member 508 is beingmoved in the living body along the vein. That is, the surface area ofthe distal end portion 510 in contact with the vein or other tissue isreduced by virtue of the existence of the window 526. It is thus easierto move the dissecting member through the living body along the vein.

There is also another benefit associated with configuring the upturneddistal end portion 510 distal end portion of the dissecting member as aframe member that surrounds a through window 526. This additionalbenefit is illustrated in FIGS. 16A and 16B. FIG. 16A illustrates theframe portion 524 of the upwardly curved distal end portion 510 of thedissecting member 508 and shows the way in which the vein 1000 is ableto be positioned in the window 526 surrounded by the frame portion 524.FIG. 16B illustrates that if the distal end portion did not include orpossess the through opening defining the window, the distal end portionof the dissecting member would contact and press against the vein 1000,thus possibly damaging the vein.

As described above, the elongated member 502 projecting proximally fromthe dissecting member 508 is a hollow elongated member, meaning thehollow elongated member possesses a lumen 528. This lumen 528 isillustrated by way of example in FIG. 15. This lumen 528 opens into thedissecting member 508, particularly the area or space 513 surrounded bythe side portions 514, the holding portions 520 and the part of themount 512 spanning the side portions 514. During use of the dissectingdevice 500, it is possible to introduce a viewing device or imagingdevice (e.g., an endoscope, camera, etc.) into the lumen 528 and advancethe viewing device along the lumen 528 to the distal open end of thelumen 528. This viewing device can then be used to view a viewing areagenerally in front of the dissecting member 508 as the dissecting memberis being moved in the living body along the vein 1000. An example of aviewing device 1002 is schematically illustrated in FIG. 15.

FIGS. 17A and 17B illustrate another benefit associated with configuringthe distal end portion or upturned member as a frame portion surroundinga window. The frame portion tends to hold the tissue (fat) 1200surrounding the vein 1000 so that the tissue may not interfere with thefield of view of the viewing device 1002 located in the lumen 528 of thehollow elongated member. On the other hand, as illustrated in FIG. 17B,in the absence of the frame portion, the tissue is free to force its wayupward together with the vein 1000 into the field of view of the viewingdevice 1002, a result that is not preferable.

A part of the upturned distal end portion 508 of the dissecting memberor the entirety of the upturned distal end portion 508 of the dissectingmember may be made transparent, for example buy being made oftransparent material. A holding portion side of the dissecting member'sdistal end portion may have a concave shape as the window. The width ofthe holding portion is thicker or greater than the width of thedissecting member.

FIGS. 18A and 18B illustrate another embodiment of the dissectingdevice. This embodiment of the dissecting device 600 includes orpossesses an elongated dissecting member 602 possessing a generallycylindrical shape and hollow configuration. The elongatedcylindrically-shaped dissecting member 602 possesses a proximal endportion 604 and a distal end portion 606. A protrusion 608 is positionedat the distal end portion 606 of the dissecting member 602. In theillustrated embodiment, the protrusion 608 is comprised of a series ofcircumferentially spaced apart and axially extending protrusions 608that alternate with circumferentially spaced apart and axially extendinggrooves. The protrusion member (alternating protrusions 608 and grooves)is an integral part of the dissecting member 602. That is, theprotrusion 608 is integrally formed in one piece as a unitary part ofthe dissecting member 602.

The protrusion 608 at the distal end of the dissecting member 602 thuscauses the distal end of the dissecting member 602 to exhibit an annularsaw tooth-shaped profile as generally illustrated in FIG. 18B. Stateddifferently, the distal end of the dissecting member 602 possesses aseries of circumferentially spaced apart axially extending notches orindents that define an annular saw tooth-shaped configuration asillustrated.

The protrusions 608 are each preferably shaped so that they possess acurved shape as seen from the end (the distal end or left end in FIG.18B). For example, the curvature (radius of curvature) of theprotrusions member 608 can be similar to the curvature (radius ofcurvature) of the outer surface of the dissecting member 602. Inaddition, the protrusion 608 possesses a limited circumferential extent,meaning that each of the protrusions is not an annular member possessinga 360° circumferential extent. The circumferential extent of theprotrusion member 608 is preferably less than 180°. A range for thecircumferential extent of the protrusions may be based on thecircumferential distance between side branches of the vein.

The dissecting device 600 further includes or possesses a cutting andheating member 612. This cutting and heating member 612 is generallyannular-shaped as seen in transverse cross-section, though does notpossess 360° circumferential extent. That is, as described below andshown in FIG. 18B, the cutting and heating member 612 is C-shaped intransverse cross-section, meaning there is a break in the cutting andheating member 612 along the circumferential extent of the heatingmember 612. This break can accommodate the guide wire. The cutting andheating member 612 is separate from and movable relative to thedissecting member 602, is positionable at the distal end portion of thedissecting member 602 and is located inside the dissecting member 602.The cutting and heating member 612 is positionable at the base (proximalend) of the saw tooth-shaped distal end of the dissecting member 602.That is, the cutting and heating member 612 is positioned at theproximal end of the notches and protrusions 608 forming the sawtooth-shaped distal end 610 of the dissecting member. As the dissectingdevice 600 is moved along the vein (saphenous vein) during use of thedissecting device, side branches of the vein, such as the side branches1100 illustrated in FIGS. 4A, 4B, 5A, 5C are received in the notchesforming the saw tooth-shaped distal end 610 of the dissecting member 602and are then cut by the cutting and heated heating member 612. In thisregard, the cutting and heating member 612 is connected to an electricallead 614 as illustrated in FIG. 18B so that the cutting and heatingmember 612 may be connected to a power source for heating the cuttingand heating member.

The dissecting member 602 is preferably a hollow elongated member (e.g.,tubular member) with a lumen extending along its length. The dissectingdevice 600 is preferably used together with a guide wire 616 asillustrated in FIGS. 18-20. During use, the guide wire 616 is positionedin the lumen in the dissecting member 602.

A tubular member 620 is rotatably mounted on the outer surface of thedissecting member 602 at two spaced apart locations 622, 622 asgenerally illustrated in FIG. 18A. That is, the tubular member 620 canbe rotated relative to the dissecting member 602. This tubular member620 also includes or possesses an elongated receiving part 624 providedwith a lumen configured to receive a viewing device or imaging devicesuch as an endoscope, camera or the like. The tubular member 620 mayhave at least part of the lumen. For example, the tubular member hasC-shape. With the viewing device 1002 positioned in the lumen of thetubular member or elongated receiving part 624, the user is able to viewa viewing area or imaging area in front of the dissecting member 602 asthe dissecting member 602 is moved through the living body along thevein.

The cutting and heating member 612 is an elongated member or possessesan elongated shape. The cutting and heating member 612 is located in thedistal end portion of the dissecting member 618. In the illustratedembodiment, the cutting and heating member 612 and the dissecting member602 are coaxial. The cutting and heating member 612 is located under thedissecting member 618 in a radial direction of the dissecting devise600. That is, as described above, the cutting and heating member ispositioned in the lumen in the dissecting member 602. The cutting andheating member 612 can be O-shaped, C-shaped or the like, and ispositioned axially behind or at the base of the grooves or notchesbetween the protrusions 608.

A method of using the dissecting device 600 to dissect a blood vessel(e.g., a vein such as a saphenous vein) may be generally similar to themethod described above in that the method may include using thedissecting device 600 to dissect the blood vessel (including tissue(fat) covering the blood vessel), ligating and cutting the blood vessel,and then removing the severed or dissected blood vessel with thesurrounding tissue from the living body. The method here involvesseveral different aspects as discussed below.

In the case of dissecting a vein (saphenous vein), for example, afteridentifying the location of the vein to de dissected, an incision ismade in the living body (e.g., the leg of a patient) to provide anaccess site to the vein as well as the saphenous fascia surrounding thevein. The user then introduces the guide wire 616 into the living bodyby way of the incision, and moves the guide wire 616 along the vein 1000in a known manner so it generally follows the vein 1000. The user maythen hold the proximal portion of the dissecting device 600 and positionthe dissecting member 602 over the guide wire 616 so that the guide wire616 is located in the lumen in the dissecting member 602. The dissectingmember 602 is then advanced in the forward direction over the guide wire616 to introduce the dissecting member 602 into the living body by wayof the incision. The dissecting member 602 (with the cutting and heatingmember 612 positioned inside the dissecting member 602) is advanced toposition the vein 1000 to be dissected into the lumen in the dissectingmember 602. The dissecting member 602 and the cutting and heating member612 are thus positioned in surrounding relation to the vein asillustrated in FIG. 21. The dissecting member 602 is then moved alongthe guide wire 616 so that the dissecting member 602 moves along thevein 1000. As the dissecting device 600 is moved along the guide wire616, the presence of the protrusion member 608 can help stabilize theguide wire 1002 because the guide wire 616 is preferably positionedimmediately adjacent the protrusion member 608. As the dissecting device600 is moved along the guide wire, the cutting and heating member 612operates to perform dissection. As the dissecting device 600 is movedalong the guide wire 616, the side branches of the vein are positionedin the grooves or notches between the protrusions 608, and are cut andheated by the cutting and heating member 612 after the side branches ofthe vein are guided between the distal end portions (grooves) of thedissecting member 618. The disclosed method thus involves cutting a sidebranch of the vein while at the same time stopping bleeding using thecutting and heating member 612.

FIG. 20 illustrates that the elongated receiving part 624 of the tubularmember 620 possesses a 360° circumferential extent. But it is alsopossible that the elongated receiving part 624 can exhibit acircumferential extent less than 360°, for example by possessing aC-shaped cross section. The tubular member 620 can thus be configureddifferently than illustrated, though should preferably be configured tobe rotatably mounted on the dissecting member 602 and to receive andhold/guide a viewing device or imaging device 1002.

The method associated with the use of the dissecting device 600 shown inFIGS. 18-21 involves inserting the dissecting member 602 between a firsttissue and a second tissue. That is, the protrusion member 608 candissect the first tissue and the second tissue from one another. Thedissecting device disclosed here is configured so that as the dissectingdevice is being advanced, the dissecting member 602 dissects thetissue/vein while the cutting and heating member 612 cuts side branchesof the vein. This occurs at the same time because the dissecting member602 and the cutting and heating member 612 are positioned relativelyclose to one another. In this embodiment, the cutting and heating member612 is axially movable. The cutting and heating member 612 is axiallymovable relative to the dissecting member 602.

FIGS. 22-26 illustrate another embodiment of the dissecting device 600′.Many of the features of this embodiment of the dissecting device 600′are similar to the embodiment of the dissecting device 600 illustratedin FIGS. 18-21, and common features between the two embodiments areidentified by common reference numerals. A detailed discussion of thefeatures associated with the dissecting device 600′ which have alreadybeen described above will not be repeated.

This embodiment of the dissecting device 600′ shown in FIGS. 22-26differs from the earlier embodiment of the dissecting device 600 in thatthe embodiment shown in FIGS. 22-26 includes or possesses a coveringmember 628 positioned in overlying or covering relation to the lumen inthe tubular member 620 that receives the viewing device 626. Thecovering member 628 possesses a cap or cover 630 connected to a mountingportion 632 that is rotatably mounted on the portion of the tubularmember 620 housing the viewing device 626. The covering member 628 alsoincludes or possesses an elongated tubular (hollow) member 634 thatprojects rearwardly (in the proximal direction) from the mount 632. Thecovering member 628 also possesses a lumen 636 that passes through themount 632 and communicates with the hollow interior of the elongatedtubular member 634. The lumen 636 possesses an open distal end thatfaces in the direction of the cap or cover 630. The lumen in thecovering member 628 is connected to a source of fluid 638 schematicallyillustrated in FIG. 22B. The fluid from the fluid source 638 passesthrough the lumen 636 and is ejected from the open distal end of thelumen to clear the field of view for the viewing device 626. The fluidsource can be any desired source of fluid, an example of which is carbondioxide (CO₂).

The covering member 628 is preferably configured so that the coveringmember overlies or covers an area immediately in front of the viewingdevice 626. The cap 630 prevents tissue from blocking the field of viewof the viewing device 626, thus allowing the dissecting member to beproperly positioned to cut or sever a side branch(es) 1200 of the vein.In addition, fluid can be introduced by way of the lumen 636 to clearaway the field of view for the viewing device 626. The covering member628 (the cap 630 and the fluid lumen) thus advantageous helps preventtissue from blocking the viewing device (e.g. endoscope, camera, etc.).The cap 630 is also configured and positioned so that an imaginarycontinuation of the viewing device 626 in the forward directionintersects at least a part of the cap of 630.

FIG. 26 illustrates one way of using the dissecting device shown inFIGS. 22-26. As illustrated, the side branch 1200 of the vein 1000 ispositionable between the cover or cap 630 and the viewing device 626.

This embodiment of the dissecting member 600′ also possesses the grooves618 constituting distal portions for receiving side branches. Thisembodiment shown in FIGS. 22-26 is configured so that the cutting member612, which is coaxial with the dissecting member 602, is positioned onthe outer surface of the dissecting ember 602 (i.e., exterior of thedissecting member 602). But it is also possible for the cutting member612 to be coaxial with the dissecting member 602 and positioned insidethe dissecting member 602.

FIGS. 22A and 22B illustrate that this embodiment of the dissectingdevice 600′ need not include a cutting and heating element. Instead, thedissecting device 600′ includes or possesses a cutting element 612. Butthe dissecting device 600′ can be provided with the heating member 612if desired as shown schematically in FIG. 25. If the dissecting device600′ is configured without the heating member, the manner of operationof the dissecting device is generally as follows. After confirming thelocation of the vein to be dissected, an incision is made in the patient(i.e., the living body) to gain access to the vein. The dissectingdevice 600′ is then introduced into the living body and moved along thevein 1000. This embodiment of the dissecting device 600′ does notnecessarily require a guide wire as in the earlier embodiment. In theearlier embodiment of the dissecting device 600, the viewing device 1002is spaced relatively far from the vein 1000 and so the guide wire isuseful in helping to guide the movement of the dissecting device 600along the vein. The embodiment of the dissecting device 600′ shown inFIGS. 22-26 is configured so that during use, the viewing device 626 ispositioned relatively close to the vein 1000. A guide wire is thuspreferably not used or necessary. As the dissecting device 600′ is movedalong the vein, the cutting device cuts fat surrounding the vein. Theviewing device used during this forward movement of the dissectingdevice can help guide the movement of the dissecting device even thoughthe cap/cover 630 of the covering member 628 may hinder the field ofview. When the dissecting device 600′ approaches a side branch 1200 ofthe vein 1000, the covering member 628 is rotated into a position likethat illustrated in FIG. 26 so that the side branch 1200 may be cutusing the cutting device 612. Thus, the viewing device 626 permitsconfirmation of the cutting of the side branch 1200. The vein can thusbe severed after one forward axial movement of the dissecting device600′.

In the embodiments of the dissecting device 600, 600′ shown in FIGS.18-26, the size of the lumen that houses the viewing device 626 (i.e.,the cross-sectional area transverse to the axis of the lumen) is largerthan the size of the lumen 630 along which fluid is directed to clearthe field of view of the viewing device.

Both embodiments of the dissecting device 600, 600′ shown in FIGS. 18-26can also utilize a dissecting member in the form of bi-polar electrodes.

FIGS. 27-29 illustrate a further embodiment of a dissecting device. Thisembodiment of the dissecting device 700 includes or possesses a cappingmember 702, a cutting member 704, and a tubular member 708. The tubularmember 708 is elongated and hollow along its entire axial extent. FIGS.27A, 27B and 29 illustrate that at least the distal portion of thetubular member 708 is provided with a cover 710 that divides theinterior of the tubular member 708 (lumen in the tubular member 708)into an upper portion (half) in which is located a first lumen 712, anda lower portion (half) in which is located a second lumen 714. The firstlumen 712 is configured to receive a viewing device or an imaging device(e.g., an endoscope, camera or the like) while the second lumen 714 isconfigured to receive an ablation device (heating device).

The cover member 710 that divides the interior of the tubular member 708into two parts maybe a clear cover member. This can help facilitateviewing a position of the vein with a viewing device and facilitatemoving the viewing device along the vein.

The capping member 702 is mounted on and fixed to the distal end portion716 of the tubular member 708. In the illustrated embodiment, thecapping member is mounted on the outer periphery of the tubular member708 so that the proximal portion of the capping member 702 encircles theouter periphery of the tubular member 708. As illustrated in FIGS. 27and 28, the capping member 702 possesses a hollow cylindrical or annularproximal portion 718 and a curvilinearly tapering distal portion 720.The proximal portion 718 encircles and is fixed to the distal endportion 716 of the tubular member 708. The distal portion 720 of thecapping member 702 is shaped as one-half of a curvilinearly taperingcone.

The cutting member 704 is mounted on the tubular member 708. In theillustrated embodiment, the cutting member 704 possesses a generallyC-shaped proximal portion 704′ that is mounted on and encircles theouter periphery of the tubular member 708 at a position proximal of thecapping member 702. The cutting member 704 is movable relative to thetubular member 708 and the capping member 702. That is, the cuttingmember 704 is movable (slidable) along a half-circle movement path fromthe position on the left side of the bottom half shown in FIG. 29 to thecorresponding position on the right side of the bottom half in FIG. 29.

As in the earlier embodiment described above and shown in FIGS. 22-26,the capping member 702 covers and protects the viewing device positionedin the first lumen 712 to prevent tissue from blocking the viewingdevice. The tapered shape of the capping member 702 allows thedissecting device 700 to be moved through the living body along the veinrelatively easily. When the dissecting device 700 being moved along thevein encounters a side branch of the vein (e.g., the side branch 1100shown in FIGS. 4A, 4B, 5A, 5B), the dissecting device 700 may bemanipulated or rotated to position the side branch inside the cappingmember 700 between the viewing device located in the first lumen 712 andthe distal-most end of the capping member 702. The viewing devicepositioned in the first lumen 712 can thus be used to view the sidebranch and facilitate the cutting of the side branch by the slidingmovement of the cutting movement 704.

The cutting member 704 is generally used to cut the side branches of thevein, though may be used throughout the dissecting procedure.

The capping member 702 possesses a window 706. This window simplyresults from the configuration of the distal portion 720 of the cappingmember 702, namely that the capping member is open along half of itscircumference. The cutting member 704 is located between the tubularmember and the capping member 702 in the radial direction of thedissecting device 700.

Referring to FIG. 29, the window spanning across the capping member 702possesses one edge at the left and another edge at the right. Thewidth-wise extent of the window thus extends from the one edge (leftedge) to the opposite edge (right edge). The cutting member 704 isturnable or slidable (rotatable) from one edge of the window to theopposite edge of the window. The window may be transparent member.

The cutting member 704 may be provided with a lumen. Such a lumen may beconfigured to receive or house an electrode and/or an ablation devicewhich serves as a heating device to help stop bleeding. The cuttingmember is also configured to move in the axial direction, and thedistal-most end of the cutting member 704 is positioned distally of(forward of) the distal-most end of the capping member 702 such asillustrated in FIGS. 27 and 28. The distal-most end of the cuttingmember 704 may also be positioned distally of (forward of) thedistal-most end of the dissecting member.

The window member may have a longitudinal opening and may betransparent. A window member may be included that covers the window 706.The longitudinal opening may be at least a part of the longitudinallength of the window member. The longitudinal a distal portion of thecapping member to this side of a proximal end of the inner surface ofthe capping member. A space can be between the window member and aninner surface of the capping member.

FIG. 30 illustrates a further embodiment of a vein harvesting device orvein dissecting device. This embodiment of the vein dissecting device800 includes or possesses an assembly of three parts or members, namelya dissecting member 802, a covering member 804 and a cutting member 806.As will be described below in more detail, during use of the veindissecting device 800, the dissecting member 802 is first positionedunder the covering member 804 and then is later removed from thecovering member 804. The cutting member 806 is then positioned under thecovering member 804.

FIG. 30 illustrates just the distal portion of the dissecting member, itbeing understood that the dissecting member 802 is an elongated memberas is apparent from, for example, the illustration in FIG. 33C. Thedissecting member 802 is shown in more detail in FIGS. 31A and 31B. Thedissecting device 802 is an elongated member which, in the illustratedembodiment, possesses a rounded and longitudinally extending centralportion 808 and two longitudinally extending lateral wings 810 onopposite sides of the central portion 808. The dissecting member 802also possesses a generally flat bottom surface 812 provided with alongitudinally extending and centrally located opening 814 thatcommunicates with and opens into a lumen 816 configured to receive aviewing device or imaging device 1002 (e.g., an endoscope, camera or thelike). The opening 814 is centrally located with respect to thewidth-wise extent of the dissecting member 802. The top surface 817 ofthe distal end portion of the dissecting member 802 is flattened asshown in FIGS. 30 and 31A to allow the dissecting member 802 to beaccommodated in the covering member 804 as shown in FIGS. 33A-33C, andso that when the dissecting member 802 and the covering member 804 areassembled as shown in FIGS. 33A-33C, a relatively smooth transitionexists between the distal end portion of the dissecting member 802 andthe distal end portion of the covering member 804.

FIG. 31B illustrates the dissecting member 802 in transversecross-section and shows the viewing device 1002 positioned in the lumen816 of the dissecting member 802. The viewing device 1002 allows thearea in front of the dissecting member 802 to be viewed while thedissecting member 802 is being advanced or moved in the forwarddirection through the living body and along the vein.

The distal-most end 818 of the dissecting member 802 is rounded as seenin FIGS. 30 and 31A to help facilitate relatively smooth movement of thedissecting member 802 through the living body and to help facilitatedissection of the vein from surrounding tissue.

FIG. 30 illustrates just the distal portion of the covering member 804,it being understood that the covering member 804 is an elongated memberas is apparent from, for example, the illustration in FIG. 33C. Thecovering member 804 is shown in more detail in FIGS. 32A and 32B. Thecovering member 804 possesses an elongated shape along its longitudinalextent and exhibits a dome-shaped configuration (somewhat hemisphericalshape) in transverse cross-section as illustrated in FIG. 32B. A hollowspace or lumen 820 is positioned at the underside of the covering member804. This hollow space or lumen 820 is specifically configured toreceive the dissecting member 802 as illustrated in FIGS. 32A and 32B.That is, after the dissecting member 802 is inserted into the livingbody, the covering member is inserted into the living body and advancedto a position covering or on top of the dissecting member 802 to formthe assembly shown in FIGS. 33A-33C. The covering member 804 may bepositioned in covering relation to the dissecting member 802 before thedissecting member 802 is positioned in living body, or after thedissecting member 802 is positioned in living body but before moving thedissecting member 802 along the vein. As described in more detail below,the hollow space or lumen 820 in the undersurface of the covering memberis also configured to receive the cutting member 806 after thedissecting member 802 is removed from the covering member 804.

As illustrated in FIG. 32A, the distal portion of the covering member804 possesses a U-shaped recess 822 that opens into and communicateswith the hollow space or lumen 820. This U-shaped recess also opens tothe distal end of the covering member 804 so that the dissecting member802 can protrude at the distal end of the covering member as shown inFIGS. 33A and 33C. That is, when the covering member 804 is positionedover or in covering relation to the dissecting member 802, the distalend portion of the dissecting member 802 protrudes through the U-shapedrecess and protrudes distally beyond the distal-most end 805 of thecovering member 804 as illustrated in FIGS. 33A and 33C.

The cutting member 806 includes or possesses an elongated member 824 anda blade 826 that are connected to one another by a connecting member828. As illustrated in FIG. 30, the elongated member 824 is a hollowmember that possesses a lumen 830 extending along the entire length ofthe elongated member 824. The lumen 830 is configured to receive aviewing device or imaging device (e.g., an endoscope, camera, etc.).This viewing device helps facilitate the use and operation of thecutting member 806 during operation of the dissecting device 800allowing the user to view the area in front of the cutting member 806.

The blade 832 is a curved blade possessing a curved (convex) outersurface 832 and an oppositely facing curved (concave) inner surface. Thecurvature of the outer surface 832 of the blade 826 is selected toclosely match the curvature on the inner surface 821 of the coveringmember. Thus, when the elongated member 824 of the cutting member 806 isrotated to rotate or turn the curved blade 826 of the cutting member 806while the blade 826 is positioned underneath the cover member 804 (i.e.,when the cutting member 806 is positioned in the underside of thecovering member 804 as shown in FIG. 34), the outer surface 832 of theblade 826 closely corresponds to and follows the curved inner surface(under surface) 821 of the cover member 804 as can be appreciated fromFIGS. 34 and 35. FIG. 35 illustrates the cutting member 806 positionedin the cover member 804 with the viewing device 1002 positioned in thelumen inside the elongated member 824. FIG. 35 also shows that theproximal end of the elongated member 824 can be connected to a handle834 or other suitable operating device to rotate or turn the blade 826of the cutting member 806.

FIG. 33C illustrates an example of the elongated nature of the coveringmember 804 positioned over the elongated dissecting member 802. FIG. 33Cillustrates that the proximal end portion of the covering member 804 canbe provided with a series of axially spaced apart ridges 807. Theseridges 807 can help facilitate holding by the user.

As described above, during use of the dissecting device 800, thedissecting member 802 by itself is first positioned in the living bodyby way of an incision formed in the living body. The dissecting member802 is then moved along the vein for a distance. The covering member 804is then introduced into the living body and positioned in coveringrelation to the dissecting member 802 as shown in FIGS. 33A-33C. Duringuse, the covering member may be pressed so that the covering memberdoesn't move. The cutting member rotates along an inner surface of thecovering member toward out of an inner cutting member to cut the veinand tissue that is surrounding the vein from the tissue.

After the dissecting member 802 is removed from the covering member 804,the cutting member 806 is introduced into the lumen 820 (the underside)of the covering member 804. FIG. 35 illustrates, in cross-section, thecutting member 806 positioned in the lumen in the underside of thecovering member 804. The cutting member 806 is preferably positioned inthe lumen 820 of the covering member 804 in a manner such as illustratedin FIG. 35 in which the cutting member 806 is positioned close to or incontact with one of the interior sides of the covering member 804. Withthe cutting member 806 positioned in such a manner, the cutting member806 may be rotated or turned to effect desired cutting.

As the cutting member 806 is introduced into the lumen 820 in theunderside of the covering member 804, the viewing device 1002 may bepositioned in the lumen 830 in the elongated hollow member 824 of thecutting member 806. This allows the cutting member 806 to be more easilyoperated or manipulated to the correct position. It is also possible tointroduce the viewing device 1002 into the lumen 830 in the elongatedhollow member 824 of the cutting member after the cutting member 806 ispositioned in the lumen 820 in the underside of the covering member 804.The viewing device 1002 can be used during the cutting operation to viewin front of the cutting blade 826.

After the cutting member 806 is introduced into the lumen 820 in theunderside of the covering member 804, it is possible to rotate theelongated member 824, or the handle 834 connected to the elongatedmember 824, to rotate or turn the blade 826. The blade 826 thus rotatesabout an axis represented by the central axis 825 of the elongatedmember 824. This rotation axis 825 is offset from the center ofcurvature of the concavely curved blade 826. Rotating or turning theblade 826 causes the blade 826 to move from the position shown in FIG.36 to the position in which tip end of the blade 826 reaches theopposite side edge 809 of the covering member 804. After the cuttingmember is rotated to cut away the tissue from the vein, the cuttingmember may be rotated back to the FIG. 36 position and then the cuttingmember may be moved forward and once again rotated. This process oroperation may be repeated.

After the desired length of the vein has been separated from thesurrounding tissue, the covering member 804 and the cutting member 806are removed from the living body, the ends of the dissected vein areligated and then cut (severed), and the severed vein is removed from theliving body for use in the desired manner.

FIG. 37 illustrates a slightly modified version of the dissecting devicedepicted in FIGS. 30-36. This embodiment of the dissecting device 900shown in FIG. 37 includes or possesses an assembly comprised of adissecting member 902, a covering member 904 and a cutting member 906.These three members 902, 904, 906 are generally similar to thedissecting member 802, the covering member 804 and the cutting member806 respectively described above, except for the following differences.

The embodiment of the elongated dissecting member 902 shown in FIG. 37is a bit more streamlined in configuration and possesses a more roundedor curved distal-most end to facilitate movement through the living bodyduring dissection of the vein. The same is also true of the coveringmember 904 as it also possesses a more streamlined and roundedappearance, particularly a more rounded distal-most end.

The cutting member 906 shown in FIG. 37 differs from the embodiment ofthe cutting member shown in FIG. 30 in that the cutting member 906possesses a cutting portion defined by a pair of axially spaced apartblades 926. The two blades 926 are axially spaced apart so that a spaceexists between the two blades as shown in FIG. 37. By virtue of thetwo-blade configuration of the cutting member 906 shown in FIG. 37, sidebranches of the vein can rather easily move between the two-bladeconfiguration and be cut by the cut portion.

The use of the dissecting device or assembly 900 shown in FIG. 37 issimilar to that described above which reference to the dissecting deviceor assembly illustrated in FIGS. 30-36.

FIGS. 38 and 39 illustrate the dissecting device 902 as seen from below.FIGS. 38 and 39 both depict the viewing device or imagining device 1002positioned in the lumen in the underside of the dissecting device 902.FIG. 38 shows that proximal end portion of the dissecting device 902 canbe provided with a guide 903. This guide 903 possesses an axiallyextending through hole that receives the viewing device 626. The throughhole in the guide 903 may be configured to relatively closely match theouter diameter of the viewing device 626 to help guide the viewingdevice 626 in the forward intended direction.

FIG. 39 generally illustrates the field of view 950 associated with theviewing device 1002. This field of view 950 allows the dissecting member902 to be moved in the living body and along the vein (saphenous vein)while viewing the location of the vein to avoid contacting and possiblydamaging the vein.

The covering member shown in FIGS. 30-33 is configured in a way thatprovides a relatively tight space at the distal end of the coveringmember. On the other hand, the configuration of the covering membershown in FIG. 36 provides a relatively larger space at the distal end.The configuration of the space can have an effect on the operability ofthe cutting member.

FIGS. 40-42 illustrate a slightly different embodiment of the coveringmember. As described above with reference to FIG. 38, the proximalportion of the dissecting member 802 includes or possesses an integrallyformed viewing device holder serving as a guide for the viewing device1002. In the embodiment shown in FIGS. 40-42, the holder for holding theviewing device is separate from and connectable to the covering member.As illustrated in FIG. 40, the proximal portion 1009 of the coveringmember 1004 is hollow and possesses a space 1007 for receiving theviewing device holder 1005. A ledge 1011 is located in the holder space1007, on opposite sides of the holder space 1007, to receive the holder1005. The flat bottom surface of the holder 1005 rests on the ledges1011 on opposite sides of the space 1007, and the curved upper surface1013 of the distal portion of the viewing device holder 1005 matches thecurved inner surface overlying the holder space 1007. Thus, when theholder 1005 is slid into the holder space 1007 as illustrated in FIG.41, the holder 1005 is supported and held in place by the ledges 1011and the overlying curved surface defining the upper boundary of theholder space 1007. After the holder 1005 is positioned in the holderspace 1007 of the covering member 1004, the viewing device 626 m may beintroduced into the lumen 1015 in the holder. The viewing device 626 isthus held in place and properly guided.

FIGS. 43 and 44 illustrate additional details associated with thecutting member 906 forming a part of the dissecting device 900 depictedin FIG. 36. The cutting member is configured so that each of the blades926 includes or possesses an electrode 952. The blades 926 also possessbipolar elements. The side branches of the vein are able to relativelyeasily come between or move between the two-blade configuration to becut by the cut portion.

The dissecting devices 952, 926 may be bi-polar electrodes.

FIG. 45 illustrates an embodiment of the cutting member in which adouble cutting portion is provided. That is, the connecting part of thecutting member is connected to the middle of the blade, and both sidesor ends of the blade are provided with triangular-shaped projections(i.e., a saw-tooth profile). The embodiments of the cutting member shownin FIGS. 30, 37 and 45 are able to cut when the cutting member is beingrotated in only one direction, whereas the embodiment of the cuttingmember shown in FIG. 45 is able to cut when the cutting member is beingrotated in either direction.

All embodiments of the device and method disclosed here can be used inoperations other than a living body. That is, the device and method canbe used with other bodies such as a cadaver and a simulator intended tosimulate the living body.

In all embodiments of the vein dissecting device and method disclosedhere, the dissecting device and method are specifically implemented todissect the layer (saphenous fascia), the vein (saphenous vein) andtissue around the vein from surrounding tissue in the living body.

The detailed description above describes embodiments of a blood vesseldissecting device and blood vessel dissecting method representingexamples of the invention disclosed here for harvesting a blood vessel(vein) for use in vascular bypass grafting. The invention is notlimited, however, to the precise embodiments and variations described.Various changes, modifications and equivalents can be effected by oneskilled in the art without departing from the spirit and scope of theinvention as defined in the accompanying claims. It is expresslyintended that all such changes, modifications and equivalents which fallwithin the scope of the claims are embraced by the claims.

What is claimed is:
 1. A vein harvesting assembly for harvesting a veinin a body, the vein harvesting device comprising: a dissecting memberpossessing a distal end portion and a proximal end portion, thedissecting member being insertable into the body and moved along a veinto dissect tissue surrounding the vein; a covering member possessing aproximal end portion and a distal end portion, the covering memberincluding a covered space extending from the proximal end portion to thedistal end portion, the covering member being mountable on and movablealong the dissecting member when the dissecting member is positioned ina living body; and a cutting member comprised of an elongated member anda blade member so that rotation of the elongated member results inturning of the cutting member to cut tissue surrounding the vein, thecutting member being insertable into the space in the covering memberand being movable in a distal direction along the space.
 2. The veinharvesting device according to claim 1, wherein the elongated memberpossesses an outer surface, the covering member possessing an innersurface facing the space, the cutting member being configured so thatduring the movement of the cutting member in the distal direction, theouter surface of the elongated member moves along the inner surface ofthe covering member.
 3. The vein harvesting device according to claim 2,wherein the inner surface of the covering member is a curved surface. 4.The vein harvesting device according to claim 1, wherein the coveringmember possessing an inner surface facing the space, the blade memberpossessing an exterior surface that moves along the inner surface of thecovering member as the cutting member moves in the distal direction. 5.The vein harvesting device according to claim 1, wherein the blademember is a curved blade member.
 6. The vein harvesting device accordingto claim 1, wherein the distal end portion of the covering memberpossesses an opening through which projects the distal end portion ofthe dissecting member when the covering member is mounted on thedissecting member.
 7. The vein harvesting device according to claim 1,wherein the blade member is comprised of a plurality of axially spacedapart blades so that a space exists between axially adjacent blades. 8.The vein harvesting device according to claim 1, wherein the blademember is a curved blade member possessing a center of curvature, theelongated member possessing a central axis that does not pass throughthe center of curvature of the blade member.
 9. The vein harvestingdevice according to claim 1, wherein the elongated member possesses alumen configured receive a viewing device which permits viewing of aviewing area in front of the blade member.
 10. The vein harvestingdevice according to claim 1, wherein the dissecting member possesses alumen configured to receive a viewing device which permits viewing of aviewing area in front of the dissecting member.
 11. The vein harvestingdevice according to claim 1, wherein the covering member is connected toa holder that is separate from, and insertable into, the coveringmember, the holder including a lumen configured to receive a viewingdevice which permits viewing of a viewing area in front of thedissecting member as the dissecting device is forward moved in the body.12. A vein harvesting method for harvesting a vein in a body, the methodcomprising: inserting a dissecting member into a living body; forwardmoving the dissecting member along a vein in the body to dissect tissuesurrounding the vein; introducing a covering member into the body andforward moving the covering member along the dissecting member so thatthe dissecting member is positioned between the vein and the coveringmember; withdrawing the dissecting member from the body while thecovering member remains in the body to create a space between thecovering member and the vein; introducing a cutting member into the bodyand forward moving the cutting member to position the cutting member inthe space; dissecting the vein using the cutting member; removing thecovering member and the cutting member from the body after the vein issevered; and removing the severed vein from the body.
 13. The veinharvesting method according to claim 12, wherein the cutting memberincludes a blade member connected to an elongated member so thatrotation of the elongated member turns the blade member, the dissectingof the vein using the cutting member comprising rotating the elongatedmember to turn the blade member and dissect the vein.
 14. The veinharvesting method according to claim 12, wherein the dissecting memberincludes a lumen extending from the proximal end portion of thedissecting member to the distal end portion of the dissecting member,the method further comprising inserting a viewing device into the lumenin the dissecting member while the dissecting member is in the body andusing the viewing device to view a viewing area in front of thedissecting member during the forward movement of the dissecting member.15. The vein harvesting method according to claim 12, further comprisinginserting a viewing device into the space between the covering memberand the vein, and using the viewing device to view a viewing area infront of the covering member.
 16. The vein harvesting method accordingto claim 12, wherein the distal end portion of the covering memberpossesses an opening, and wherein the covering member is forward movedalong the dissecting member so that the distal end portion of thedissecting member is positioned in the opening and is exposed outsidethe covering member.
 17. The vein harvesting method according to claim12, wherein the cutting member possesses a blade member connected to anelongated member, the elongated member possessing a central axis, theblade member is a curved blade member possessing a center of curvature,the dissecting of the vein using the cutting member including rotatingthe elongated member to cause the blade member to rotate about an axisthat does not pass through the center of curvature.
 18. The veinharvesting method according to claim 12, further comprising inserting aholder into a proximal end portion of the covering member, the holderincluding a lumen, and inserting a viewing device into the lumen in theholder after the holder is inserted into the covering member, and usingthe viewing device to view a viewing area in front of the coveringmember.